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$xhtml = array(
	'<{title}>' => 'Notes',
	'<{subtitle}>' => 'Written in <span title="Online Education Strategies">UNIV 1001</span> of <a href="http://www.uopeople.edu/">University of the People</a>, finalised on 2016-10-12',
	'<{copyright year}>' => '2016',
	'takedown' => '2017-11-01',
	'<{body}>' => <<<END
<h2>Notes on nuclear energy</h2>
<h3>The nature of atoms:</h3>
<ul>
	<li>
		Uranium:
		<ul>
			<li>
				Discovered in 1789
			</li>
			<li>
				Discovered by Martin Klaproth, a German chemist
			</li>
			<li>
				Named after Uranus (the planet, not the Roman god)
			</li>
			<li>
				Uranium can be split into smaller elements such as barium:
				<ul>
					<li>
						Huge amounts of energy are released by this fission.
						<ul>
							<li>
								This energy is in heat form, but can be used to generate electricity.
							</li>
						</ul>
					</li>
				</ul>
			</li>
		</ul>
	</li>
	<li>
		Radiation:
		<ul>
			<li>
				Ionizing radiation:
				<ul>
					<li>
						Ionizing radiation is produced as continuous X-rays by passing electrical current through a vacuum-filled glass tube.
					</li>
					<li>
						Discovered in 1895
					</li>
					<li>
						Discovered by Wilhelm Rontgen
					</li>
				</ul>
			</li>
			<li>
				Radiation can destroy bacteria.
			</li>
			<li>
				When alpha or beta particles are released, a new element is formed.
			</li>
			<li>
				Some elements have many radioactive isotopes, called radionuclides:
				<ul>
					<li>
						Many radionuclides occur naturally and ban be used as tracers with simple instruments.
					</li>
				</ul>
			</li>
		</ul>
	</li>
	<li>
		Pitchblende:
		<ul>
			<li>
				Pitchblende is an ore containing radium and uranium:
				<ul>
					<li>
						Pitchblende radium and polonium:
						<ul>
							<li>
								Pierre and Marie Curie isolated polonium and radium from pitchblende in 1898.
							</li>
							<li>
								Radium can be used in medical treatment.
							</li>
							<li>
								Alpha particles fired from radium at nitrogen cause the formation of oxygen.
							</li>
						</ul>
					</li>
				</ul>
			</li>
			<li>
				Pitchblende causes photographic plates to darken due to the pitchblende&apos;s radiation.
			</li>
			<li>
				Pitchblende is radioactive:
				<ul>
					<li>
						Alpha radiation (helium nuclei)
					</li>
					<li>
						Beta radiation (electrons)
					</li>
					<li>
						Gama radiation:
						<ul>
							<li>
								similar to X-rays
							</li>
							<li>
								probably a type of electromagnetic radiation
							</li>
						</ul>
					</li>
				</ul>
			</li>
		</ul>
	</li>
	<li>
		Neutrons:
		<ul>
			<li>
				James Chadwick discovered neutrons in 1932.
			</li>
			<li>
				Neutrons can create a wider variety of radionuclides can be formed by bombarding atoms with neutrons than protons.
			</li>
		</ul>
	</li>
</ul>
<h3>Nuclear fission:</h3>
<ul>
	<li>
		Fission releases neutrons which cause a chain reaction.
		Massive amounts of energy are released that way:
		<ul>
			<li>
				This chain reaction doesn&apos;t normally sustain itself.
			</li>
			<li>
				To sustain itself, a mixture of uranium and water can be used:
				<ul>
					<li>
						The water slows down the neutrons ejected from fission so that they are slow enough to cause the next atoms to undergo fission.
					</li>
					<li>
						A neutron-absorbing material can also be added to avoid exponential multiplication of neutrons:
						<ul>
							<li>
								This can stabilize the reaction enough for use in nuclear power plants, where you don&apos;t want explosions.
							</li>
						</ul>
					</li>
					<li>
						Uranium oxide and heavy water might be needed.
						<ul>
							<li>
								The water only has to be heavy water if the uranium isn&apos;t enriched enough.
							</li>
						</ul>
					</li>
					<li>
						Sustaining the reaction means that the neutron output is higher than the neutron input.
					</li>
					<li>
						Graphite can also be used instead of water.
					</li>
				</ul>
			</li>
		</ul>
	</li>
	<li>
		Fission is easier to instigate in uranium-235 than in uranium-238.
		<ul>
			<li>
				However, uranium-235 is also much less common than uranium-238.
				<ul>
					<li>
						0.7% of uranium is uranium-238 while 99.3% is the less-useful uranium-238.
					</li>
					<li>
						Increasing the ratio of uranium-238 to uranium-238 is referred to as &quot;enrichment&quot;.
					</li>
				</ul>
			</li>
			<li>
				Uranium-238 is more likely to form into uranium-239 instead of splitting:
				<ul>
					<li>
						Uranium-239 breaks down into neptunium-239 (element 93) by emitting an electron:
						<ul>
							<li>
								Neptunium-239 (element 93) breaks down into plutonium-239 (element 94) by emitting an electron:
								<ul>
									<li>
										Plutonium can be split with fast or slow neutrons.
									</li>
									<li>
										It is easier to separate Plutonium from uranium than separate the two naturally-occurring types of uranium from one another.
									</li>
									<li>
										Plutonium has a greater half life than uranium.
									</li>
								</ul>
							</li>
						</ul>
					</li>
				</ul>
			</li>
		</ul>
	</li>
	<li>
		Slow neutrons instigate fission more readily than fast-moving neutrons.
	</li>
</ul>
<h3>Concepts:</h3>
<ul>
	<li>
		Frisch-Peierls Memorandum:
		<ul>
			<li>
				Written by Peierls and Frisch
			</li>
			<li>
				Predicted that five kilograms of pure uranium-235 could cause a massive explosion
				<ul>
					<li>
						Equivalent to several thousand tonnes of dynamite
					</li>
				</ul>
			</li>
			<li>
				Suggested how to detonate this mass
			</li>
			<li>
				Suggested how to produce this much pure uranium-235
				<ul>
					<li>
						Thermal diffusion can separate uranium-235 from uranium-238
					</li>
				</ul>
			</li>
			<li>
				Estimated the effects of the radiation caused by such a bomb
			</li>
		</ul>
	</li>
	<li>
		The problems of creating uranium gas and pure uranium metal were studied in Birmingham University and Imperial Chemical Industries.
	</li>
	<li>
		Uranium hexafluoride gas was first produced by Philip Baxter.
	</li>
	<li>
		Uranium oxide and heavy water were used to sustain a chain reaction.
	</li>
	<li>
		At one point, Peierls predicted that eight kilograms, not five, were needed.
		<ul>
			<li>
				However, this could be reduced using neutron deflectors.
			</li>
		</ul>
	</li>
	<li>
		12 kilograms of uranium-235 is equivalent to 1,800 tons of TNT:
		<ul>
			<li>
				We don&apos;t know how much a &quot;ton&quot; is, because there are British tons and United States tons.
			</li>
			<li>
				A ton is not equal to a tonne.
			</li>
		</ul>
	</li>
	<li>
		Radioisotopes produced through nuclear fission can be used as a substitute for radium.
	</li>
	<li>
		Three methods of enrichment:
		<ul>
			<li>
				Electromagnetic separation
			</li>
			<li>
				Centrifuge method
			</li>
			<li>
				Gaseous diffusion
			</li>
		</ul>
	</li>
	<li>
		There were ten secret nuclear cities in the Soviet Union.
	</li>
	<li>
		Different countries had different nuclear strategies:
		<ul>
			<li>
				The United States used a boiling water reactor.
			</li>
			<li>
				Canada used natural uranium and heavy water.
			</li>
			<li>
				France used a gas-graphite design.
			</li>
			<li>
				The Soviet Union used a boiling water graphite channel reactor.
			</li>
			<li>
				Sosnovy Bor used a high-power channel reactor.
			</li>
			<li>
				Kazakhstan used a fast neutron reactor (prototype).
			</li>
			<li>
				Most countries use light-water reactors.
			</li>
		</ul>
	</li>
	<li>
		Nuclear energy is better than fossil fuels as far as carbon output.
		<ul>
			<li>
				Personally though, I think that Nuclear energy shares a problem with fossil fuels: scarcity.
			</li>
			<li>
				We&apos;ll run out of uranium just like we&apos;ll run out of oil and coal.
			</li>
			<li>
				Is there a safe way to dispose of nuclear waste from power plants?
			</li>
		</ul>
	</li>
</ul>
<h2>Usefulness of notes and why I chose outline-style notes for this assignment</h2>
<p>
	I can&apos;t stand Cornell-style notes.
	For one thing, they&apos;ve never been an effective note-taking strategy for me.
	In high school, I had a teacher that swore by them, and required that all of their students take Cornell-style notes and hand them in, but this actually caused me to do very poorly in the course.
	In addition to Cornell-style notes being ineffective for me, they&apos;re a bit long-winded, so I didn&apos;t have time to take both the graded Cornell notes and notes in a format that I&apos;d actually find useful.
	While this note-taking strategy may be effective for some people, it&apos;s not for everyone.
	There&apos;s no one-size-fits-all approach to taking notes! It&apos;s worth noting that my teacher&apos;s version of Cornell notes wasn&apos;t exactly like the version discussed in this week&apos;s readings and these notes were harder to manage.
	However, there&apos;s another issue with Cornell notes for me now that I&apos;m on a computer.
	For me, the most effective way to write and store notes is as plain text (TXT) files.
	I have a large directory on my machine dedicated just to notes on various topics, and really, I wouldn&apos;t be able to keep track of everything if these notes were in a more complex file format.
	Cornell notes require two columns to be used, which in plain text format, leads to major amounts of editing to keep everything formatted correctly whenever you make changes to the note contents.
</p>
<p>
	Likewise, the mapping strategy isn&apos;t for me.
	The readings suggest that it&apos;s a great option for visual learners, but I&apos;m a tactile learner.
	Also, again, it doesn&apos;t work well in a plain text file.
	The charting strategy is also for visual learners and doesn&apos;t work well in a plain text file.
	I&apos;ve been known to occasionally convert my notes into XHTML for a more visually-appealing note set, but mapping and charting would require lots of time and would leave me with notes that are less than helpful for my learning style.
	I&apos;m not sure that I really understand the flow method and the write-on-the-slides method is even bulkier  and harder to process than other note-taking formats, especially when in a digital medium.
	The know-want-learn method seems like it might be effective for some, but often times, I don&apos;t know what I want to learn before reading the material.
</p>
<p>
	The sentence strategy seems very much like the strategy that I use when writing up my daily journal entries.
	As the day&apos;s events unfold, I write various sentences about what is going on, then at the end of the day, I organize like concepts together, then form them into paragraphs.
	The main part that I don&apos;t normally do is numbering the sentences, as there&apos;s no particular need to do that in regards to my journal.
	The outline method is closer to what I use for my journal entries when I&apos;m not feeling well, don&apos;t have much time, or am otherwise not going to be able to write and publish the journal entry on time, though I use a very skeletal version.
	I typically use an informal version of one of these two styles when I&apos;m taking notes for an essay that I need to write as well.
	As should go without saying, both of these note-taking styles lend themselves very well to storage as plain text files.
</p>
<p>
	Of these two note-taking methods that are effective for my learning style and use case, I chose to take notes for this assignment in the outline style, as I can keep it organized as I go (unlike the sentence strategy, which involve writing disorganized notes and then later organizing them) and it doesn&apos;t involve numbering the sentences.
	I find numbering unordered informational sentences to be a strange concept and not of much use.
	I thought that there might be a trans-formatting issue.
	Outline-style notes make heavy use of spaces for indentation, but in XHTML/HTML, multiple spaces in a row aren&apos;t rendered.
	I thought that upon submission, all of my spacing would be lost.
	However, University of the People&apos;s submission form seems to have programmed to account for that and fixes the problem.
	It also has a direct $a[XHTML]-entering option that I just discovered today, so I was able to clean my notes up even further before submitting them.
</p>
<p>
	This note-taking strategy would be great for helping me prepare for an exam because it keeps related ideas grouped together.
	Instead of using the organization of the original document, I was able to structure my notes into a tree that better fit how I understood the topic of nuclear energy.
	Studying these notes, I should be able to retain the information better than by just rereading the original article.
	The original article had certain pieces of similar information scattered in different sections due to when they were chronologically discovered, but grouping all of that together offers a more clear look at our current understanding of the topic.
</p>
END
);
